Level 3
One minute ago, 80% of the students in a parade square were girls. 143 more students entered the parade square. As a result, the number of girls increased by 40% and the number of boys increased by 60%. How many students are in the parade square now?

Level 3
Eva's salary is 30% more than Betty's salary. When their salaries are increased by 60%, their combined salaries will be $11040. How much was Eva's salary before the increase?

Level 3
A basket contained violet and purple buttons. There were 60% more violet buttons than purple buttons. When 248 more buttons were poured into the basket, the amount of violet buttons increased by 40% and the amount of purple buttons grew by 60%. How many buttons were in the basket at first?

Level 3
On Monday, 700 more youths than children attended a concert. On Tuesday, the number of youths decreased by 30% and the number of children increased by 80%. 1240 audience attended the concert on Tuesday. If each ticket cost $12, how much money was collected from the sale of concert tickets for the two days?

Level 3
Last month Mr Zhang gave his wife, Anna $4000 for household expenditure. Anna spent 60% of the sum on rental, 30% on food and saved the rest. This month, Mr Zhang reduced the sum he gave to Anna. Anna spent the same amount on rental and reduced the amount she spent on food by 30%. She saved the remaining 10% of the sum given to her this month. By what percentage was the sum given to Anna reduced?